arXiv:1512.06102 · Physical review. B./Physical review. B
Spectral function of the two-dimensional Hubbard model: A density matrix renormalization group plus cluster perturbation theory study
Chun Yang, Adrian E. Feiguin
Abstract
We study the spectral function of the two-dimensional Hubbard model using cluster perturbation theory, and a density matrix renormalization group as a cluster solver. We reconstruct the two-dimensional dispersion at and away from half-filling using $2\ifmmode\times\else\texttimes\fi{}L$ ladders, with $L$ up to 80 sites, yielding results with unprecedented resolution in excellent agreement with quantum Monte Carlo. The main features of the spectrum can be described with a mean-field dispersion, with kinks and pseudogap traced back to scattering between spin and charge degrees of freedom.